Various chitosan-containing materials and chitosan derivatives have been used for surgical repair or drug delivery. Documents relating to such materials or derivatives include U.S. Pat. No. 6,514,522 (Domb), U.S. Pat. No. 6,602,952 B1 (Bentley et al.) and U.S. Pat. No. 7,053,068 B2 (Prinz), U.S. Patent Application Publication No. US 2005/0238702 A1 (Ishihara et al.), Canadian Patent Application No. 2 348 842 A1 (Bernkop-Schnürch), Published PCT Application No. WO 98/31712 A2 (B.F. Goodrich Co.), Aspden et al, Chitosan as a Nasal Delivery System: The Effect of Chitosan on In Vitro and In Vivo Mucociliary Transport Rates in Human Turbinates and Volunteers, J Pharm Sci, 86, 4, 509-513 (1997), Costain et al., Prevention of postsurgical adhesions with N,O-carboxymethyl chitosan: Examination of the most efficacious preparation and the effect of N,O-carboxymethyl chitosan on postsurgical healing, Surgery, 121, 3, 314-319 (1997), Mi et al., Synthesis and Characterization of a Novel Chitosan-Based Network Prepared Using Naturally-Occurring Crosslinker, J Polym Sci, Part A: Polym Chem, 38, 2804-2814 (2000), Mi et al., Synthesis and characterization of biodegradable TPP/genipin co-crosslinked chitosan gel beads, Polymer, 44, 6521-30 (2003), Roldo et al., Mucoadhesive thiolated chitosans as platforms for oral controlled drug delivery: synthesis and in vitro evaluation, European Journal of Pharmaceutics and Biopharmaceutics, 57, 115-121 (2004), Krauland et al., Viscoelastic Properties of a New in situ Gelling Thiolated Chitosan Conjugate, Drug Development And Industrial Pharmacy, 31, 885-893 (2005), Bernkop-Schnürch, Thiomers: A new generation of mucoadhesive polymers, Advanced Drug Delivery Reviews, 57, 1569-1582 (2005), Bernkop-Schnürch et al., Thiomers: Preparation and in vitro evaluation of a mucoadhesive nanoparticulate drug delivery system, International journal of Pharmaceutics, 317, 76-81 (2006), Hong et al., Covalently crosslinked chitosan hydrogel: Properties of in vitro degradation and chondrocyte encapsulation, Acta Biomaterialia, 3, 1, 23-31 (2007) and Weng et al., Rheological Characterization of in Situ Crosslinkable Hydrogels Formulated from Oxidized Dextran and N-Carboxyethyl Chitosan, Biomacromolecules, 8, 1109-1115 (2007).